Concrete form

ABSTRACT

A concrete form adapted to remain in place after associated concrete that has been poured into the concrete form has cured generally includes a first concrete panel, a second concrete panel and a tie rod. The second concrete panel is spaced from the first concrete panel to define a volume between the first panel and the second panel. The tie rod attaches to the first and second panels. The tie rod limits the movement of the first panel with respect to the second panel when associated concrete is poured into the volume.

BACKGROUND OF THE INVENTION

Concrete forms retain uncured concrete as it is being poured and while the concrete sets. As seen in FIG. 1, known concrete forms A are typically configured with wood or aluminum panels B, wailers C and steel tie rods D. The concrete form is assembled by positioning the panels B in a desired location to define the periphery of the concrete structure that is to be formed. The panels typically define the lateral surfaces of the desired structure.

Wailers C, which are typically wooden horizontal members that run the entire periphery of the concrete form, are abutted against an external surface of the panels. The wailers provide rigidity to the panels and, along with the tie rods, counteract the horizontal forces that are exerted on the panels by the uncured concrete.

The steel tie rods D extend through openings in the wailers and in the panels to firmly hold the wailers against the panel. The steel tie rods extend through the interior of the concrete form to attach a wailer and panel to another wailer and panel that is located across from the aforementioned wailer and panel. One end of the tie rod includes a head that sandwiches the wailer to the panel. An opposite end of the tie rod includes an internally threaded opening. A threaded fastener is inserted into an opening in the wailer and in the panel and is received inside the internally threaded opening in the steel tie rod. The threaded fastener is tightened inside the threaded opening to secure the wailer to the panel and the panels to one another.

Concrete is then poured into the concrete form. After the concrete has cured, the form is disassembled and can sometimes be reused. The threaded fasteners that are received in the threaded openings of the steel tie rods are removed and the panels are disassembled.

Certain problems are inherent with such a concrete form. For example, the wooden and aluminum panels are expensive and typically do not have a very long life. Also, wailers need to be used with known concrete forms to counteract the pressure of the uncured concrete as it is poured into the form. If the concrete structure that is to be formed is placed inside of an excavation, for example a footing for a foundation or the like, excavation beyond the periphery of the concrete structure is required so that the fasteners and wailers required with the known concrete form can be fit inside of the excavation. As seen in FIG. 1, the excavation must also provide adequate room for a construction worker to maneuver to disassemble and remove the concrete panels, which is depicted as dimension X. Typically this requires a much greater excavation for safety concerns, e.g. a drawing back of the sides of the excavation so that the soil is disposed at an angle 0. Furthermore, removal of the fasteners used to connect the wailers and the panel to the steel tie rods can be difficult and sometimes require the construction worker to cut the fastener that connects the wailer and the panel to the steel tie rod when the fastener cannot be unscrewed.

When using concrete forms having wood panels, many transportation project specifications require that these wood panels be removed since the wood is an organic material that can degrade. Accordingly, it typically is not an option to leave the concrete form in place after the concrete structure has been poured. Also, typically these concrete forms are formed at the construction job site. Automated steel tying tools that are used to tie rebar that is set inside the concrete structure are typically delicate. On site tying of the rebar risks damage or loss of these expensive steel tying tools. Less automated steel tying tools can be used; however, using these less automated steel tying tools can increase the time, and thus increase the cost, of tying the steel rebar.

SUMMARY OF THE INVENTION

A concrete form adapted to remain in place after associated concrete that has been poured into the concrete form has cured generally includes a first concrete panel, a second concrete panel and a tie rod. The second concrete panel is spaced from the first concrete panel to define a volume between the first panel and the second panel. The tie rod attaches to the first and second panels. The tie rod limits the movement of the first panel with respect to the second panel when associated concrete is poured into the volume.

In addition to describing a concrete form, a method of assembling a concrete form and accompanying rebar for a concrete structure away from a site where the concrete structure is to be poured includes the following steps: connecting reinforced concrete panels to construct a concrete form; positioning rebar in relation to the concrete panels such that when concrete is poured into the concrete form the concrete at least partially surrounds the rebar; and connecting the rebar to the concrete panels such that the rebar and the concrete panels can be lifted together as an assembly.

A concrete form and rebar assembly adapted to be assembled away from a construction site generally includes a plurality of connected panels, a plurality of tie rods, and rebar. The panels define a volume into which associated concrete is poured to form a concrete structure. The tie rods extend through the volume connecting at least some of the panels to one another. The rebar attaches to at least one of the tie rods or at least one of the panels in a manner to allow the rebar, the connected panels and the tie rods to be lifted as a single assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation view of a known concrete form disposed in an excavated area that is shown in cross section.

FIG. 2 is a perspective view of a concrete form.

FIG. 3 is a perspective view, partially broken away, of a panel for use with a concrete form such as that depicted in FIG. 1.

FIG. 4 is an elevation view of an alternative embodiment of a concrete form disposed in an excavated area that is shown in cross section.

FIG. 5 is a perspective view of another embodiment of a concrete form.

FIG. 6 is a perspective view of another embodiment of a concrete form and rebar attached to the concrete form.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with an embodiment shown in FIG. 1, a concrete form 10 generally includes panels 12 that are connected to one another by tie rods 14. The depicted concrete form 10 is similar to known concrete forms in that the panels 12 typically define lateral peripheral surfaces of a concrete structure that is to be formed. As seen in FIG. 2, the concrete form 10 can be open ended having only lateral side panels. The concrete form 10 can take numerous configurations, including configurations that cannot be typically achieved with known concrete forms. Concrete is poured between the side panels 12 to form the desired concrete structure. As opposed to concrete forms that include panels that are made of wood or aluminum, for construction projects that require the removal of wooden or metal panels the concrete form as described herein can remain in the ground after the concrete has cured. Accordingly, labor savings is achieved as compared to known concrete forms because the concrete panels 12, which will be described in more detail below, do not need to be removed.

With reference to FIG. 3, the panel 12 includes concrete 16, or another composite material, having a fine reinforcement mesh 18 and a large rigid reinforcement mesh 22 disposed in the concrete. Accordingly, the panel 12 can be referred to as a reinforced concrete, or reinforced composite material, panel. Typically the reinforcement meshes 18 and 22 are covered by the concrete 16 on both sides so that the reinforcement mesh is not visible or exposed to the elements. In the embodiment depicted in FIG. 3, the reinforcement mesh is made of steel that is formed or tied in a rectangular cross pattern as shown in FIG. 3. The meshes 18 and 22 are designed to accommodate at least some of the tensile forces that will be placed on the panel 12 during pouring of the concrete inside the concrete form 10 and while the concrete sets. The tensile forces are a result of the horizontal pressure forces that are exerted by the uncured concrete, which are typically carried by the wailers and tie rods in known concrete forms. Even though the meshes 18 and 22 are depicted in a rectangular cross pattern, the meshes 18 and 22 can take other configurations. Also, the meshes 18 and 22 can be made of other materials that can be used to reinforce the concrete 16 of the panel 12, such as plastic, a composite material, or the like. Also, the meshes 18 and 22 can be provided as a single unit, or more than two or perhaps no reinforcing members or meshes can be provided in the reinforced panel 12.

To make the panel 12, a template (not shown), which is typically a wooden or metal frame having a bottom wall or panel attached to the frame, is provided having a peripheral configuration that matches, for example, the thinner peripheral edges of the panel 12 shown in FIG. 3. One of the reinforcement meshes, either the fine reinforcement mesh 18 or the large reinforcement mesh 22, is cut to fit within the wooden frame and placed inside the frame. The other of the meshes is cut to the proper dimensions and also placed inside the frame. To make the panel 12 depicted in FIG. 3, the meshes 18 and 22 are cut so that they fill the entire frame. Alternatively, the meshes, or other reinforcing members, can be cut to fill only a portion of the frame. Concrete, or another composite material, is then poured into the frame and the meshes 18 and 22 are pulled up into the concrete spacing the meshes from the floor of the frame so that when the concrete cures the meshes are covered by concrete, or the other composite material, all the way around the meshes.

It has been found that it is desirable to use a low slump concrete and to vibrate the concrete into the area between the meshes 18 and 22 when manufacturing panels. Nevertheless, it is possible to manufacture the panels using a high slump concrete that flows more easily around the meshes.

The large lateral surfaces of the panel 12, for example in the panel depicted in FIG. 2, are smoothed in a known manner to provide a large smooth lateral surface for the panel. By providing a smooth lateral surface for the panel 12, the uncured concrete that abuts the panel does not adhere to the panel. Accordingly, for the depicted concrete form 10 the concrete panel 12 does not become a structural component of the final concrete structure.

The concrete panels can be formed to have different thicknesses and different lengths. As one example, concrete panels that have a height less than 18″ can have a thickness of about 1″ and a length up to about 10 feet. A panel having a height less than 48″ can have a thickness of about 1.25″ and a length up to about 40 feet. As another example, a concrete panel having a height between about 48″ and about 72″ can have a thickness of about 2″ and a length up to about 40 feet.

With reference back to FIG. 2, a plurality of tie rods 14 are used to secure the panels 12 to one another. The tie rods 14 extend through the interior of the concrete form and remain inside the concrete after it has cured. In the depicted embodiment, the tie rods 14 extend generally normal to each side panel; however, the tie rods 14 can extend at an angle other than normal. The tie rods can be made from steel and do not require the threaded ends that are required by the tie rods used in known concrete form systems.

As opposed to wailers that are used with known concrete forms, retaining members 24, such as washers, are used to fix the location of the panel 12 in relation to the tie rod 14 and other panels. The washers 24 are affixed to the tie rod 14, and can be affixed permanently, via welding or the like, as opposed to known concrete forms that use fasteners to selectively attach to tie rods. Instead of washers, plates, clips or similar retaining member can be used. For retaining members that abut the interior surface of the panel 12, it may be desirable to provide an opening for receiving the tie rod 14. As mentioned above, in the depicted embodiment, the concrete form 10 does not need to use wailers. Instead, retaining members 24 abut external and internal surfaces of each of the panels 12. Unlike wailers, the retaining members 24 in the depicted embodiment do not completely surround the periphery of the concrete form 10; however, if desired the retaining members can comprise an angle iron, or similar member, that can surround at least a majority of the periphery of the form. Also, the retaining members 24 that attach to the tie rods 14 are considerably thinner than the wailers that are used with known concrete forms, known wailers typically comprising two 2″×4″ boards that are fastened to one another.

To attach one panel to another, a washer 24, or other retaining member, is attached at or near an end of the tie rod 14. The tie rod 14 is then inserted through an opening (not visible in FIG. 2) that is formed in the panel 12. The opening can either be formed when making the panel, i.e. forming the panel from the concrete as described above, or the opening can be later drilled through a cured panel. After the tie rod 14 has been inserted through the opening, a washer 24 is then attached to the tie rod 14 to abut an interior surface, i.e. a surface of the panel that will contact the poured concrete. The tie rod 14 is then inserted through an opening in another panel 12. Washers are then welded on an exterior surface and an interior surface of the other panel. The panels 12 are then affixed to one another and fixed along the length of the tie rod. Since the washers 24, or other retaining members, permanently attach to the tie rods 14, the tie rods can be made from a stock material that can be cut to the desired length. The stock material is much less expensive than known tie rods.

Assembling a concrete form 10 will be described in more detail with reference to FIG. 4. The concrete form 10 shown in FIG. 4 is disposed inside an excavated area 30, e.g. a hole, where soil 32 or other material have been removed. The excavated area 30 can be referred to as being stepped, in that the area includes a first deeper lower surface 34 and a second shallower lower surface 36. Where construction specifications require the removal of wooden form panels, the concrete form 10 depicted in FIG. 4 does not need to be removed from the excavated area 30 after the concrete that will be placed inside the form has cured. This is because the reinforced concrete panels of the concrete form 10 are not organic.

As seen in FIG. 4, the concrete form 10 depicted in that figure includes three panels: a first panel 12 a, a second panel 12 b, and a third panel 12 c, all of which are similar to the panel 12 depicted in FIG. 3. The first panel 12 a includes a lower edge 38 a that rests on the deeper lower surface 34 of the excavated area 30 and an upper edge 42 a that is spaced above the lower edge. The second panel 12 b is horizontally spaced from the first panel 12 a and connected to the first panel by a tie rod 14, in a manner that has been described above. The second panel 12 b includes a lower edge 38 b that rests on the deeper lower surface 34 of the excavated area 30 and an upper edge 42 b that is spaced above the lower edge 38 b. The upper edge 42 b of the second panel 12 b is disposed below the upper edge 42 a of the first panel 12 a and is generally parallel with the shallower lower surface 36 of the excavated area 30. The third panel 12 c is horizontally spaced from the second panel 12 b such that the second panel 12 b is disposed between the first panel 12 a and the third panel 12c. The third panel 12 c includes a lower edge 38 c that rests on the shallower lower surface 36 of the excavated area 30 and an upper edge 42 c that is spaced above the lower edge. In the embodiment depicted in FIG. 4, the third panel 12 c attaches to the first panel 12 a via tie rods 14 in a manner that has been described above.

With continued reference to FIG. 4, concrete is placed or poured into the concrete form 10 into a volume 44 defined between the panels 12 a, 12 b and 12 c, and any end panels that may attach to the panels. A job specification requiring a portion of a footing to have a certain depth below grade while not requiring the entire footing to have such a depth below grade, such as the stepped excavation 30 depicted in FIG. 4, typically could not be achieved using a form that requires removal of the panels. This is because there is no access for a worker to remove the second panel 12 b once the concrete has been poured into the volume 44 of the concrete form 10. Using a concrete form having wooden or metal panels would require excavation of the soil between the second panel and the third panel down to the deeper lower surface 34 since the second panel is inaccessible once the concrete has been poured into the form. However, with the described concrete form 10, one that does not employ wooden panels but instead reinforced concrete panels, the second panel 12 b can remain after the concrete has cured so that the required volume of concrete to make the concrete structure has been reduced. This can result in substantial savings when making footings having different elevations below grade.

Wooden panel concrete forms may be used to form a stepped concrete structure, such as that shown in FIG. 4, by performing two separate pours at two different times. For the first pour the concrete is poured between the first panel and the second panel and allowed to cure. The second panel is then stripped from the concrete structure and then in the second pour concrete is poured between the first panel and the third panel. This construction method requires additional time, which may not be available if the construction project is on a tight time schedule, for example a bridge replacement project.

Furthermore, the excavation that is required for a footing can be reduced using the described concrete form 10 as opposed to the known concrete form. Since the tie rods 14 attach to washers 24 that abut the panels 12, further excavation is not required to accommodate wailers, as opposed to known concrete forms. Also, since the panels 12 stay in place after the concrete has set, no further excavation is required to accommodate a worker to disassemble the concrete form 10, as opposed to known concrete forms. This is more noticeable when comparing FIG. 1 to FIG. 4.

With reference to FIG. 5, a concrete form 10 having panels 12 d, 12 e, 12 f and 12 g is shown. In this embodiment, bent rods 50 attach adjacent panels, for example panel 12 d to panel 12 e. Where the panel is at a right angle, such as that shown in FIG. 5, the bent rod 50 is also disposed at a right angle. Adjacent panels can be at other angles and the bent rod can be bent to conform to those other angles. The bent rods 50 extend through openings (not visible) in each panel and can attach via a washer or other retaining member 52. In the depicted embodiment, expansion joint filler 54 is interposed between abutting edges of adjacent panels for example disposed between an end of panel 12 e and a lateral interior surface of panel 12 d. The expansion joint filler 54 is the same type of expansion joint filler that is used in between concrete joints for sidewalks, driveways and the like. Expansion joint filler can be used with the other embodiments of concrete forms that have been described above.

Tie rods 14 and retaining members 24, e.g. washers, are used to attach panels that are disposed opposite one another, for example panel 12 d and panel 12 f. As mentioned above, the concrete form can take many other configurations. Furthermore, the panels are shown as having a smooth interior surface. Where the concrete panel has a smooth interior surface, the concrete that is poured into the concrete form is not designed to adhere to the concrete form. However, in an alternative embodiment, the concrete form can include a roughened interior surface so that the concrete that is poured into the concrete form can more easily adhere to the concrete panel.

With reference to FIG. 6, a concrete form 10 having rebar 60 already placed in the form can be assembled off site and moved to the construction site, for example via a tractor trailer. Similar to the embodiments described above, the concrete form includes a plurality of reinforced concrete panels 12 that are connected to one another using tie rods 14 and bent rods 50. The concrete form 10 is assembled according to project specifications at a location away from the construction site, for example at a remote manufacturing facility. The rebar 60 is placed inside the concrete form 10 according to project specifications. Since the concrete form 10 and the accompanying rebar 60 are assembled off site, typically in a controlled environment such as a factory, delicate steel tying tools can be used to tie the rebar 60 mitigating the risk of damage to the steel tying tools, as compared to tying the steel rebar at the construction site. The steel rebar 60 attaches to the concrete form 10, for example to the panels 12 and/or the tie rods 14, so that the concrete form 10 and the accompanying rebar 60 can be lifted as an assembled unit onto a tractor trailer.

To lift the assembled unit, a lifting member 70, for example a piece of timber, is positioned inside the concrete form 10 underneath at least some of the tie rods 60. A plurality of straps (not shown) are then wrapped around the lifting member and attached to an excavator (not shown), or other piece of machinery that can lift the assembled unit. The excavator is then used to lift the assembled unit. Alternatively, lifting lugs, or other members, can attach to at least one of the concrete panels 12, the tie rods 14 and the rebar 60 to lift the assembled unit. The lifting lugs, or other known hook-like device, can also be embedded in the concrete panels 12. Once the concrete form 10 and the accompanying rebar 60 reach the construction job site, the assembly is lifted off of the tractor trailer and placed in its proper location per the construction job specifications in the same manner as it was placed on the tractor trailer.

A concrete form and a concrete form and rebar assembly has been described with reference to certain embodiments. Modifications and alterations will occur to those upon reading and understanding the detailed description. The invention is not limited to only those embodiments described; instead, the invention is defined by the appended claims and the equivalents thereof. 

1. A concrete form adapted to remain in place after associated concrete that has been poured into the concrete form has cured, the form comprising: a first concrete panel; a second concrete panel spaced from the first concrete panel to define a volume between the first panel and the second panel; a tie rod attached to the first and second panels, the tie rod being adapted to limit the movement of the first panel with respect to the second panel when associated concrete is poured into the volume.
 2. The concrete form of claim 1, wherein the first panel includes a substantially smooth interior surface that contacts the associated concrete.
 3. The concrete form of claim 1, further comprising a first retaining member attached to the tie rod and contacting an exterior surface of the first panel and a second retaining member attached to the tie rod and contacting an interior surface of the first panel.
 4. The concrete form of claim 3, further comprising a third retaining member attached to the tie rod and contacting an interior surface of the second panel and a fourth retaining member attached to the tie rod and contacting an exterior surface of the second panel.
 5. The concrete form of claim 3, wherein each of the retaining members is permanently secured to the tie rod.
 6. The concrete form of claim 5, wherein each of the retaining members comprises a washer.
 7. The concrete form of claim 1, wherein the first panel includes an upper edge and a lower edge, the second panel includes an upper edge and a lower edge, the concrete form further comprising a third panel having an upper edge and a lower edge, wherein the upper edge of the second panel is disposed below the upper edge of the first panel such that when then associated concrete is poured into an area that is defined between the first and third panels at least some of the associated concrete is disposed above upper edge of the second panel while being retained by the first and the third panel.
 8. The concrete form of claim 1, wherein the at least two panels include reinforcing members embedded in concrete.
 9. A method of assembling a concrete form and accompanying rebar for a concrete structure away from a construction site where the concrete structure is to be poured, the method comprising: connecting reinforced concrete panels to define a concrete form; positioning rebar in relation to the concrete panels such that when concrete is poured into the concrete form the concrete at least partially surrounds the rebar; and connecting the rebar to the concrete form such that the concrete forms and the rebar can be lifted together as an assembled unit.
 10. The method of claim 9, further comprising placing the assembly onto a truck and delivering the assembly to a construction site.
 11. The method of claim 9, further comprising placing a removable lifting member at least partially inside the concrete form such that lifting the lifting member results in lifting the assembled unit.
 12. The method of claim 9, wherein the connecting reinforced concrete panels step comprises connecting the reinforced concrete panels using a tie rod that extends through an interior of the concrete form.
 13. The method of claim 12, wherein the connecting the rebar step further comprises tying the rebar to the tie rod.
 14. The method of claim 9, wherein the reinforced concrete panels include a substantially smooth interior surface such that the concrete panels do not form a part of the concrete structure.
 15. A concrete form and rebar assembly adapted to be assembled away from a construction site, the assembly comprising: a plurality of connected panels defining a volume into which associated concrete is poured to form a concrete structure, each panel comprising a composite material and reinforcing members disposed in the composite material; a plurality of tie rods extending through the volume connecting at least one of the panels to another panel; and rebar attached to at least one of the tie rods or at least one of the panels in a manner to allow the rebar, the connected panels and the tie rods to be lifted as an assembled unit.
 16. The assembly of claim 15, further comprising first and second retaining members permanently fixed to at least one of the tie rods, the first retaining member disposed adjacent an external surface of at least one of the panels and the second retaining member disposed adjacent an internal surface of the at least one panel.
 17. The assembly of claim 16, wherein the retaining members are welded to the at least one tie rod.
 18. The assembly of claim 15, further comprising bent rods attaching a first panel of the plurality of panels to a second panel of the plurality of panels.
 19. The assembly of claim 15, wherein an interior surface of each of the concrete panels is at least substantially smooth. 